S08 - Session O1 - Catharanthus roseus morpho-physiological response to a poly- and dichromatic light spectra in vertical farming systems

Authors: Marisa Sofia Coelho Lourenco *, Ep Heuvelink, Susana M. P. Carvalho

Madagascar periwinkle ( C. roseus ) plants are able to produce anti-cancer compounds through its secondary metabolism. C. roseus is then an added value medicinal plant, whereas have a short growing cycle (around 10 weeks) and does not grow tall in height during this time (in average 20-25 cm) making this crop highly suitable for vertical farms. The present research aimed to investigate how four different light treatments: (a)Dichromatic: (1) RB: Red (660nm) + Blue (450nm) in a ratio 2:1, with a total photosynthetic photon flux density of 150umol/m 2 s for 16h; (2) RB+UV: RB with additional 2h NUV (365nm, 10mW/m 2 ); and (b)Polychromatic:(3) WHT: White LED, with a total photosynthetic photon flux density of 150umol/m 2 s for 16h; and (4) WHT+UV: WHT with additional 2h NUV (365nm, 10mW/m 2 ) interacted with three different C. roseus cultivars (Sunstorm Apricot (S-APR), Cora XDR Polka Dot (C-XDR-POLK) and Cora Red (C-RED)) regarding their morpho-physiological responses and to further investigate its anti-cancer alkaloids production. Plants were grown for 28 days in climate chambers with 24.5ºC and with 80% relative humidity. Different light spectra did not have an impact on final plant height (cm), Leaf area (LA, cm 2 ), total dry matter (g) nor chlorophyll content. Mainly, S-APR showed to be the less robust plant having 0.20g and 0.28g less final total dry matter (TDM) comparing with C-XDR-POLK and C-Red, respectively. S-APR LA was 24% and 38% smaller comparing with C-XDR-POLK and C-Red, respectively. Additionally, S-APR was also 1.10 and 2.80 cm shorter than C-XDR-POLK and C-Red, respectively. Interestingly, generative organs were 36% lesser in C-XDR-POLK than the remaining cultivars. Root shoot ratio was 11% higher in C-RED under WHT while comparing with WHT+UV. In conclusion, S-APR shows a weaker morphological response with a lower TDM. Besides that, the C-RED and C-XDR-POLK showed a great adaptability to a vertical farming system, being the C-RED de faster developing cultivar needing approximately four days less to have all batch achieving flowering stage comparing with C-XDR-POLK. Further analysis will be done in these plants to evaluate the secondary metabolism response to the different light spectra used.